Mangonesailor
I'm Awesome
As long as all the cylinders are above 100 and within ~10% of each other that's fine.
Get some carb cleaner or anything really to spray on those leaks and see if it causes the truck to stumble, if it does then that's probably the root of your problem.
Just remember to do this with the IAC or the TPS unplugged. If you don't then the computer will compensate via the IAC and the motor will never rev up when the carb cleaner gets sucked in.
Also, OP, I noticed there is RTV around the exhaust manifold gaskets... do you know if your motor has been taken apart before?